1. Field of the Invention
The present invention relates to armor materials, and more particularly to a light-weight, high strength structural armor member for improving the capability of such armor members to resist penetration by high-speed projectiles.
2. Background of the Invention
Conventional armor is typically made of ceramic materials, metallic materials or a combination of the two. An example of conventional armor, shown in U.S. Pat. No. 4,404,889 to Miguel, includes layers of high density steel honeycomb, balsa wood, and ballistic resistant nylon sandwiched in various arrangements between outer layers of steel armor plate.
Ceramic materials offer significant efficiency in defeating armor piercing projectiles at the lowest weight per square foot of surface area. The ceramic armor sections are generally mounted on a tough support layer such as glass reinforced plastics. Boron carbide, silicon carbide and alumina are ceramics which are commonly used in armor plating.
However, ceramic plates have the serious drawback of being unable to sustain and defeat multiple hits by armor piercing projectiles. Because relatively large sections of ceramic material must be used to stop these projectiles and because these sections shatter completely when hit by a projectile, the ceramic armor is unable to defeat a second projectile impacting close to the preceding impact. Moreover, sympathic shattering of adjacent ceramic sections usually occurs, still further increasing the danger of penetration by multiple rounds.
In addition, ceramic armors are difficult and costly to manufacture; not only are very high manufacturing temperatures required, but also processing is time consuming because very slow cooling is necessary to avoid cracking.
Metallic materials have been implemented for light weight armor applications because they possess excellent ability to defeat multiple, closely spaced impacts of armor piercing projectiles. However, this class of materials is often far heavier than desired and difficult to fabricate into intricate contours. Moreover, the weight of metallic materials has typically precluded its extensive use in such light-weight mobile weapons systems as helicopters and small water craft.
While neither of these materials systems, by itself, can achieve the results of the other, heretofore their implementation in combination has also failed to achieve the totality of desired results.